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PART 4 RedLesigIling the Worl~pllace What can be done to aid people whose declining vision interferes with working? To begin with, visual tasks may be more complex at the workplace than they seemed in the doctor's office. For example, because the range of clear vision in an older person is extremely small for nearby objects" things start to go out of focus an inch or two from the optimal distanceusing video display terminals may be especially troublesome. The screen, the keyboard, and the material teeing typed are all at different distances, and none corresponds to the distance at which one usually holds a book or newspaper. Separate optical corrections may have to be prescribed for video display and reading tasks, although the two activi- ties seem similar. If an older worker is confronted with new equipment or a new visual task, a new set of bifocals or progressive focal lenses may be required. In fact, if the work site can be inexpensively redesigned so that all critical visual tasks lie within the tightly limited range of good vision of the elderly worker, job efficiency and comfort might both be enhanced. Coloring the 3~b High-contrast images are usually easiest to see. Older workers may therefore have difficulty viewing the green-on-black lettering of a typical video display terminal. Older people often lose sensitivity to blues and greens. Reds and yellows, which are easier to see, could be used instead whenever a color accent is needed. Loss of contrast is another problem for older workers, especially those with cataracts or glaucoma. The ability to distinguish between light and dark shadings may be particularly crucial for navigat- ing stairs, since the riser and tread are usually the same color. Contrast- ing strips of red or yellow, or other bright colors, may make the steps more visible. A similar use of colors can make it easier to distinguish among desktop articles or machine parts that have low contrast. Placing a piece of yellow cellophane on top of a note written in blue ink will darken the This chapter includes material from presentations at the conference by Sara Czaja, Timothy Salthouse, James Fozard, and Alan Lewis. 27

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lettering, thereby increasing the contrast between the ink and the paper and making the message legible. Light and Glare Extra lighting can dramatically improve the visual ability of older workers, particularly those with macular degeneration. The smaller opening of an older adult's pupil welcomes added light, yet because glare is a problem for the elderly, spot lighting should not be provided indis- criminately. In the same way that bright light streaming through a supermarket window can make it difficult to read the lettering on packages, a lamp backlighting an object may cause difficulty in focusing. More than ~ ,500 years ago, the Chinese monk Song Yun cited the effects of glare in his Travel Notes: "Light radiation off snow dazzles l l DISEASES OF THE RETINA Impairment of the macula, a yellowish area in the center of the retina that provides sharp central vision, is the leading cause of severe visual impairment among people age 65 and over. The most common type of macular degeneration begins late in life, usually after age 60. Known as age-related, or senile, macular degeneration, this disorder takes two forms. About 90 percent of older patients have the less severe dry form, character- ized by white or yellow Jumps that form under the macula and can destroy light-sensitive cones. Although most patients retain useful vision, there is no effective treatment for the problem. About 10 percent of patients have the more serious wet, or neovascular, form of the disease. In this disorder, fragile blood vessels grow beneath the macula, leaking blood and fluid into the central region of the retina and eventually destroying nerve cells. Serious visual impairment can result, but this type of degenera- tion may be treated with laser therapy if caught early. Early warning signs of wet degeneration are blind spots in the central field of vision and the appearance of straight lines as wavy. A simple self-test, conducted daily, can detect these prob- lems. Covering one eye at a time, a person focuses on an object with straight lines, such as train tracks or a telephone pole. Any perception of waviness should be checked by a specialist. Alterna- tively, a similar test can be performed using a card printed with a special grid pattern, called the Amsler grid. Again covering each eye in turn, vision is focused on a dot in the center of the grid. Any apparent waviness or gaps in the grid should be followed up by an eye examination. 28

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people's eyes so that they are unable to see." More recently, sensitivity to glare has boosted the popularity of the typoscope, an inexpensive gadget that aids some partially sighted older people in reading print. The device is merely a black or dark gray piece of rectangular cardboard with a window cut out of its center. The window is large enough to frame a few lines of type when placed over a printed page, the rest are blocked by the black or gray cardboard. The dark outline of the typoscope usually makes it a little easier for older people to read print, probably because it eliminates light scatter and glare from other lines of type. On-the Job Experience, Refraining, and Compensating for Impaired Vision The possibility of retraining older workers, whether they have good eyesight or not, is often overlooked. The stereotype still persists that older people are either incapable of or uninterested in learning new tasks, but there is encouraging evidence to negate this image. In the laboratory, Timothy Salthouse of the University of Mis- souri found that, in response to a visual cue, older typists were slower to strike a letter on the keyboard than younger workers. On the job, however, the older typists were as fast as their younger counterparts. The explanation? Researchers discovered what the laboratory test overlooked: older, more experienced typists were more likely to look ahead to the next word to be typed and position their fingers on the keyboard accordingly. This helped them gain speed and make up for their slower reaction time. Only when workers were prevented from viewing the next word did older typists perform more slowly than their younger colleagues. New evidence has led some scientists to believe that older work- ers, given the chance, can compensate for declining visual function by relying on learning ability and acquired skills. In addition, job retraining and compensation for impaired vision may be more important now than ever, as microscope work, operation of video display terminals, and other visually demanding jobs proliferate. Training older workers in skills needed for a new job speeds up learning. One study showed that becoming familiar with the relative sizes of machined parts, for example, helped older workers grasp the fundamentals of inspecting parts. According to Czaja, more research is needed to match job training with the specific task at hand. A 1984 study showed, for example, that commercially available training methods to teach word processing were not effective for older learners. "Unless we develop effective retraining strategies, older persons will not fit into the new work environment," Sara Czaja, SUNY-Buffalo, comments. 29

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